WO2018235524A1

WO2018235524A1 - Micro fluid device

Info

Publication number: WO2018235524A1
Application number: PCT/JP2018/020171
Authority: WO
Inventors: 一彦今村; 延彦乾; 正太郎小原; 隆昌河野; 辰典 ▲高▼松; 亮馬石井
Original assignee: 積水化学工業株式会社
Priority date: 2017-06-19
Filing date: 2018-05-25
Publication date: 2018-12-27
Also published as: CN110622007A; EP3644065A1; CN110622007B; US20210121881A1; EP3644065A4; JP2019002858A; JP6339274B1

Abstract

Provided is a micro fluid device which enables a fluid to be dosed reliably into a branch flow passage, and enables a prescribed amount of the fluid to be dispensed reliably into a plurality of branch flow passages. In a micro flow device 11, a micro flow passage 11 includes a main flow passage 12 and branch flow passages 15 to 17. The main flow passage 12 has a first flow passage expanding portion 12d, and the branch flow passages 15 to 17 have second flow passage expanding portions 15c to 17c. With regard to a T value represented by formula (1), a difference (TB-TE) between a TB value, which is the T value for the branch flow passages, and a TE value, which is the T value for the main flow passage, is at least equal to 5. Formula (1): T={1/(x2·R)}·(θ/90) In formula (1), x is a flow passage width at the starting points of the first and second flow passage expanding portions, and R is the radius of curvature of curved surface shaped parts of the first and second flow passage expanding portions. θ represents a central angle with respect to an arc having a radius of curvature R and having the starting point of the corresponding first or second flow passage expanding portion and an end point of the corresponding flow passage expanding portion as end portions.

Description

Microfluidic device

The present invention relates to a microfluidic device having an injection-molded body of synthetic resin.

Various microfluidic devices have been proposed for biochemical analysis and the like. In order to send the fluid and stop it at a predetermined portion, it is necessary to provide the microchannel with a portion having a different sending resistance. Patent Document 1 below discloses a structure in which a flow path enlargement portion is provided to rapidly expand the flow channel cross section of the microchannel. It is supposed that the fluid can be stopped by the increase in the resistance to liquid transfer in the flow path enlarged portion.

Japanese Patent Publication No. 2002-527250

In the above-mentioned microfluidic device, injection moldings of synthetic resin are widely used to achieve miniaturization and cost reduction. In order to manufacture such a synthetic resin injection-molded body, it is necessary to make the inner surface of the flow path into a curved shape at the inflection point where the flow path of the flow path expanding part changes rapidly. Otherwise, it will be difficult to remove the injection molded body from the mold.

However, when the vicinity of the inflection point becomes a curved surface, the curvature radius of the curved surface portion causes a difference in the flowability of the fluid. Therefore, for example, in the case where the main flow path is provided with the flow path expanding portion and the branch flow path is provided with the flow path expanding portion, the fluid may not be reliably weighed on the branch flow path side. That is, there is a possibility that the fluid may flow out to the downstream side from the branch flow path as the weighing unit.

Further, even in the case of dispensing the fluid into the plurality of branch channels, there is a possibility that the fluid can not be reliably dispensed into each branch channel.

An object of the present invention is to provide a microfluidic device capable of reliably performing measurement of fluid into a branch flow channel and dispensing of fluid into a plurality of branch flow channels.

A microfluidic device according to the present invention is a microfluidic device having an injection molded body made of synthetic resin and provided with a microchannel, wherein the microchannel is a downstream side of a branch portion and a branch portion. And is connected to the main flow path having the first flow path enlargement portion that increases the flow path resistance, and the branch portion of the main flow path, and is provided downstream of the branch portion And the branch flow path having the second flow path expansion portion where the flow path resistance is increased, and the inner surface of the flow path is curved in the first and second flow path expansion portions, The channel width at the start point of the first and second channel expanding parts is x, the radius of curvature R when the curved channel inner surface is viewed in plan is R, and the first and second channel expanding parts In a circular arc of radius R whose end is the start point and the end points of the first and second channel enlargements Assuming that the central angle to be set is θ, for the T value represented by the following equation (1), the TB value which is the T value for the branch flow channel and the TE value which is the T value for the main flow channel The difference satisfies TB-TE ≧ 5.

T = {1 / (x ² · R)} · (θ / 90) (1)

In a specific aspect of the microfluidic device according to the present invention, a plurality of the branch portions are provided, and a plurality of branch flow paths are connected to the plurality of branch portions in a one-to-one relationship, respectively. For the path, TB-TE ≧ 19 is satisfied. In this case, the fluid can be reliably dispensed into the plurality of branch channels.

In another particular aspect of the microfluidic device according to the present invention, a connection channel connecting the second channel expansion parts of the plurality of branch channels is further provided.

According to still another specific aspect of the microfluidic device according to the present invention, the waste fluid part connected to the first channel enlargement part is further provided.

In another specific aspect of the microfluidic device according to the present invention, the branch flow channel is connected to the upstream side of the second flow channel expansion section, and the second flow channel expansion section and the branch flow There is further provided a constriction where the flow path is narrower than the rest of the path.

In still another particular aspect of the microfluidic device according to the present invention, a liquid transfer means provided upstream of the main flow path is further provided.

According to the microfluidic device according to the present invention, in a microfluidic device having an injection molded body, a predetermined amount of fluid is reliably weighed in the branch flow channel, or a predetermined amount of fluid is reliably measured in the plurality of branch flow channels. It becomes possible to dispense.

FIG. 1 is a perspective view showing the appearance of a microfluidic device according to an embodiment of the present invention. FIG. 2 is a schematic plan view for explaining a microchannel of a microfluidic device according to an embodiment of the present invention. FIG. 3 is a schematic plan view for explaining the channel width x, the radius of curvature R, and the angle θ. FIG. 4 is a schematic cross-sectional view showing a direction in which the flow channel cross section is enlarged. FIG. 5 is a schematic plan view for explaining a curved surface-like portion in the flow passage enlarged portion in the case of the angle θ = 120 °. FIG. 6 is a schematic plan view for describing a curved surface-like portion in the flow passage enlarged portion when the angle θ = 60 °.

Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

FIG. 1 is a perspective view showing the appearance of a microfluidic device according to an embodiment of the present invention. The microfluidic device 1 has a substrate 2 made of an injection-molded body of synthetic resin. The cover sheet 3 is laminated on the substrate 2, and the base sheet 4 is laminated on the lower surface of the substrate 2. The cover sheet 3 and the base sheet 4 are made of an elastomer or an inorganic synthetic resin. A microchannel is provided in the substrate 2.

In addition, a micro flow path means the fine flow path which a micro effect arises, at the time of conveyance of a liquid (micro liquid).

In such a microchannel, the liquid is strongly affected by surface tension, and behaves differently from the liquid flowing in a normal large-sized channel.

The cross-sectional shape and size of the microchannel are not particularly limited as long as the above-mentioned micro effect occurs. For example, when using a pump or gravity when flowing a fluid in a microchannel, the cross-sectional shape of the microchannel is generally small (including a square) from the viewpoint of reducing channel resistance. In the dimension of one side, 20 micrometers or more are preferable, 50 micrometers or more are more preferable, and 100 micrometers or more are more preferable. From the viewpoint of miniaturization of the microfluidic device, the dimension of the smaller side is preferably 5 mm or less, more preferably 1 mm or less, and still more preferably 500 μm or less. In the case where the cross-sectional shape of the microchannel is generally circular, the diameter (short diameter in the case of an ellipse) is preferably 20 μm or more, more preferably 50 μm or more, and still more preferably 100 μm or more. From the viewpoint of miniaturizing the microfluidic device, the diameter (in the case of an ellipse, the short diameter) is preferably 5 mm or less, more preferably 1 mm or less, and still more preferably 500 μm or less.

On the other hand, for example, when using a capillary phenomenon effectively when flowing a fluid in a microchannel, when the cross-sectional shape of the microchannel is substantially rectangular (including a square), the dimension of the smaller side Is preferably 5 μm or more, more preferably 10 μm or more, still more preferably 20 μm or more, preferably 200 μm or less, and still more preferably 100 μm or less.

As shown in FIG. 2, the microchannel 11 has a main channel 12. On the upstream side of the main flow path 12, a micro pump 13 as a liquid feeding means is provided.

The main flow path 12 is provided with a plurality of branch parts 12a to 12c. In addition, the first flow path enlarged portion 12d is provided on the downstream side of the portion where the branch portions 12a to 12c are provided. The first flow passage enlarged portion 12 d is a portion where the flow passage cross section of the main flow passage 12 is rapidly expanded. The first flow path expanding portion 12 d determines the liquid transfer resistance of the fluid transported through the main flow path 12.

The waste liquid portion 14 is connected to the first flow path expanding portion 12 d.

Branching channels 15 to 17 are connected to the branching portions 12a to 12c, respectively. The branch flow channels 15 to 17 have branch flow channel main portions 15a to 17a connected to the branch portions 12a to 12c. After branching, flow passage narrowing portions 15b to 17b are connected to downstream ends of the branch flow passage main portions 15a to 17a. Second channel enlarged portions 15c to 17c are connected to downstream end portions of the after-branching channel narrowed portions 15b to 17b. The downstream end portions of the second flow

path expanding portions

15 c, 16 c, and 17 c are connected to the connection flow path 18. Further, a bypass flow passage 19 is provided so as to connect the first flow passage enlarged portion 12 d and the connection flow passage 18.

The size of the flow passage cross section of the after-branch flow

passage narrowing portion

15b, 16b, 17b is the branched flow which is the remaining portion of the second flow passage enlarged

portions

15c, 16c, 17c and the

branch flow passages

15, 16, 17. It is smaller than the flow passage cross section of the

passage body portions

15a, 16a, 17a. Further, the second flow passage

enlarged portions

15c, 16c and 17c are portions where the flow passage cross-sections are rapidly expanded, thereby giving a fluid resistance to the fluid in the respective

branched flow passages

15, 16 and 17.

The feature of this embodiment is that TB-TE is set to 5 or more, more preferably 19 or more, with respect to the T value represented by the following formula (1). The TB value is a T value in the second flow

path expanding portions

15 c, 16 c, 17 c of the

branch flow paths

15, 16, 17, and the TE value is a T value in the first flow path expanding portion 12 d of the main flow path 12. It is a value.

T = {1 / (x ² · R)} · (θ / 90) (1)

The T value will be described with reference to FIG. FIG. 3 is a schematic plan view showing, in an enlarged manner, a portion in which the after-branch channel narrowed portion 15b of the branch channel 15 and the second channel enlarged portion 15c are connected as one representative example. Here, the channel width x in the equation (1) refers to the channel width (in μm) at the start point 15c1 of the second channel enlarged portion 15c.

In the second flow passage enlarged portion 15c, the flow passage cross section gradually becomes larger. Here, since the substrate 2 made of an injection-molded body is used, it is necessary that the inner wall of the flow path is curved like the second flow path enlarged portion 15 c in order to perform the injection molding. . In the second flow passage enlarged portion 15c, the radius of curvature when the curved surface portion is viewed in plan is R (unit: μm). And, θ (°) is a central angle with respect to the arc Ra of the radius R with the start point 15c1 and the end point 15c2 of the second flow path enlargement part 15c as the end. Thus, in FIG. 3, θ is 90 °.

In the enlarged flow path portion, the cross section of the flow path in the second enlarged flow path portion 15c gradually increases in plan view, but as shown by arrows A and B in FIG. As shown by arrows C and D, the cross section of the flow path is gradually changed in the lateral direction as well.

In FIG. 3, the angle θ = 90 °. FIGS. 5 and 6 are schematic plan views showing curved surface-shaped portions of the second channel enlarged portion 15c in the case of θ = 120 ° and 60 °, respectively. As shown in FIG. 5, the arc Ra of the radius R has the start point 15 c 1 and the end point 15 c 2 as ends. And in FIG. 5, central angle (theta) with respect to this circular arc Ra is 120 degrees. Further, in FIG. 6, the central angle θ with respect to the arc Ra is 60 °.

In the microfluidic device 1, a predetermined amount of fluid is weighed in the

branch channels

15, 16, 17 by setting the TB-TE to 5 or more, more preferably 19 or more in the microchannel 11. Also, a predetermined amount of fluid can be reliably dispensed into the

branch flow channels

15, 16, 17. This will be described based on the following experimental example.

(Experimental examples 1 to 16)
A microfluidic device 1 was prepared in which a cover sheet 3 and a base sheet 4 were laminated on a substrate 2 which is an injection-molded body made of a cycloolefin polymer. In this microfluidic device 1, a microchannel 11 having two branched

channels

15 and 16 was provided with various dimensions. Table 1 below shows the design parameters of the flow path enlargement used as the first and second

flow path enlargements

12d, 15c, and 16c. T1 to T36 in Table 1 indicate the numbers of the flow path enlargement parts.

As Experimental Examples 1 to 16, as shown in Table 2 below, each of the second channel enlarged portions and the first channel enlarged portion was made to have dimensions indicated by T numbers, and each microfluidic device 1 was manufactured. Table 2 shows the TB value and the TE value together.

As shown in Table 2, for example, in the experimental example 1, the TB value of the branch flow channel is 125 since the flow channel enlarged portion of T29 is included. On the other hand, in the experimental example 1, the TE value is 10.2 because it has the flow path enlarged portion of T11. Therefore, TB-TE is 114.8.

As described above, microfluidic devices 1 of Experimental Examples 1 to 16 different in TB-TE were manufactured.

An aqueous solution with a contact angle of 90 ° was fed into the microfluidic device 1 using a micropump 13. When a predetermined amount of fluid could be dispensed into the two

branch flow channels

15 and 16, the results of dispensing were circled in Table 3 below. In the case where it was not possible to reliably dispense a predetermined amount of fluid into the plurality of

branch flow channels

15 and 16, x was attached.

As apparent from Table 3, it can be seen that when TB-TE is 19 or more, the fluid can be reliably dispensed into the

branch channels

15 and 16.

(Experimental example 17-32)
Next, one microfluidic device was manufactured in the same manner as described above for the branched flow channel. That is, the microfluidic device 1 was manufactured in the same manner as the experimental examples 1 to 16 except that only one branch flow channel 15 was connected to the main flow channel and the branch flow channel 16 was not provided. The TB values of the branched flow channels were the same as in Experimental Examples 1 to 16, respectively, to fabricate the microfluidic device 1 of Experimental Examples 17 to 32. Then, in the same manner as in Experimental Examples 1 to 16, an aqueous solution with a contact angle of 90 ° was fed, and it was confirmed whether or not a 5 μL amount of fluid could be reliably weighed in one branch channel. In the case where the weighing was surely performed, O was attached to Table 4 below, and when the weighing was not surely performed, X was added.

As apparent from Table 4, it can be seen that when TB-TE is 5 or more, it is possible to reliably measure a predetermined amount of fluid in one branch flow channel.

The fluid that can be used is not particularly limited, but if the fluid has a contact angle in the range of 70 ° to 130 °, the fluid can be reliably weighed or separated according to the present invention as in the above-mentioned Experimental Examples 1 to 32. It has been confirmed that it can be poured.

DESCRIPTION OF SYMBOLS 1 ... Microfluidic device 2 ... Substrate 3 ... Cover sheet 4 ... Base sheet 11 ... Micro flow path 12 ... Main flow path 12a-12c ... Branching part 12d ... 1st flow path enlargement part 13 ... Micro pump 14 ... Waste liquid part 15 ... 17 Branching Channel 15a to 17a Branching Channel Main Body 15b to 17b After Branching Channel Narrowing Section 15c to 17c Second Channel Expanding Section 15c1 Starting Point 15c2 Ending Point 18 Connecting Channel 19 ... Bypass flow path

Claims

A microfluidic device comprising an injection-molded body made of a synthetic resin and provided with a microchannel,
The microchannel is
A main flow path having a branch portion and a first flow path enlargement portion provided downstream of the branch portion and increasing flow path resistance;
A branch flow path having a second flow path enlargement portion connected to the branch portion of the main flow path, provided downstream of the branch portion, and in which the flow path resistance is increased;
The inner surface of the flow passage is curved in the first and second flow passage expanding portions, and the flow passage width at the start point of the first and second flow passage expanding portions is x, and the curved flow passage The radius of curvature where the radius of curvature when the inner surface is viewed in a plan view is R, and the start point of the first and second channel enlarged portions and the end point of the first and second channel enlarged portions are end portions Assuming that the central angle of the arc with respect to the arc of R is θ, a TB value which is a T value for the branch flow channel and a TE value which is a T value for the main flow channel are obtained for T values shown in the following equation (1) The microfluidic device, wherein the difference from the value satisfies TB−TE ≧ 5.
T = {1 / (x 2 · R)} · (θ / 90) (1)
A plurality of the branch portions are provided, a plurality of branch flow channels are respectively connected to the plurality of branch portions in a one-to-one manner, and TB-TE ≧ 19 is satisfied for each of the branch flow channels. The microfluidic device according to Item 1.
The microfluidic device according to claim 2, further comprising a connection channel connecting the second channel enlargements of the plurality of branch channels.
The microfluidic device according to any one of claims 1 to 3, further comprising a waste liquid connected to the first flow path widening part.
The branch flow channel is connected to the upstream side of the second flow channel expansion section, and a constriction section whose flow channel is narrower than the second flow channel expansion section and the remaining portion of the branch flow channel is further added. The microfluidic device according to any one of the preceding claims, which is provided.
The microfluidic device according to any one of claims 1 to 5, further comprising a liquid feeding means provided upstream of the main flow channel.